What are the structural differences between viruses and cells? Check all of them that apply. There is more than one. a) No organelles
b) No cell membrane
c) No nucleus
d) No DNA

Blood has traveled from the heart to the toes. which describes the next step of the circulation process?

Photosynthesis uses co2 and cellular respiration produces co2. we call the point when the two processes are in balance--when there is no net production of co2--the compensation point. how might you limit one of the processes in order to achieve a compensation point?

Ascience research group is testing a new type of plant food. one trial is conducted in a controlled experiment. the data from the trial show that the plant that received the new food grew faster than the control plant. the group announces that the new plant food makes plants grow faster. what is the main weakness in this scientific claim?